Updated on 2024/01/10

写真a

 
NISHIZAWA Hiroshi
 

Degree

  • Dr. Eng.   Thesis ( 2001.9   Osaka University )

Research Interests

  • Monte-Carlo simulation

  • uncertainty

  • response function

  • environment radioactivity

  • radiation behavior analysis

  • inverse problem

  • radiation measurement

Research Areas

  • Energy Engineering / Nuclear engineering  / environment radioactivity

  • Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Measurement engineering  / radiation measurement

Education

  • Osaka University   Faculty of Engineering   Department of Nuclear Engineering   Graduated

    1988.4 - 1992.3

  • Osaka University   Graduate School of Engineering   Department of Nuclear Engineering   Master's Course   Completed

    1992.4 - 1994.3

Research History

  • Industrial Electronics & Systems Laboratory, Mitsubishi Electric Corp.   Sensing Systems Development Department   Researcher

    1994.4 - 2002.3

  • Advanced Technology R&D Center, Mitsubishi Electric Corp.   Sensor Information Processing Technology Department   Chief Researcher

    2002.4 - 2016.3

  • Energy Systems Center, Mitsubishi Electric Corp.   Development Department   Technical Support Staff

    2016.4 - 2021.4

  • Fukui University of Technology   Department of Applied Nuclear Technology   Professor

    2021.5

 

Papers

  • Radioactivity Measurement System Using a Sodium Iodide Scintillator Applying an Unfolding Processing Method Reviewed

    H.Nishizawa, M.Hayashi, T.Azuma, Y.Watanabe and T.Kin

    Jpn. J. Health Phys.   49 ( 1 )   45 - 47   2014.3

  • Position-sensitive detectors based on carrier drift using a CdTe semiconductor Reviewed

    H.Nishizawa, R.Nishiura and K.Takashima

    Nuclear Instruments and Methods in Physics Research A   521   416 - 422   2004.4

  • Improvement of the Spectral Response in Large CdTe Detectors Operating at Low Bias Voltage Reviewed

    H.Nishizawa, H.Inujima and T.Takashima

    IEEE Transactions on Nuclear Science   49 ( 4 )   2025 - 2031   2002.8

  • Response calculation of a stacked CdZnTe detector for 16N γ-ray measurement Reviewed

    H.Nishizawa, H.Inujima, T.Usami, H.Fujiwara and H.Nakamura

    Nuclear Instruments and Methods in Physics Research A   463   268 - 274   2001.5

  • A Cd1-xZnxTe γ-ray Detector Sensitive in High Energy Regions Reviewed

    H.Nishizawa, K.Ikegami and T.Usami

    T. IEE Japan   118-E ( 3 )   187 - 192   1998.3

Presentations

  • Characteristic evaluation of gamma-ray spectrometer using an unfolding method with refined response functions International conference

    Masateru Hayashi, Makoto Sasano, Tetsushi Azuma, Taisuke Makita, Masakazu Nakanishi, Hiroshi Nishizawa

    THE 11TH INTERNATIONAL SYMPOSIUM ON RADIATION SAFETY AND DETECTION TECHNOLOGY (ISORD-11)  2023.7  ISORD-11 Committee

    　More details

    In order to achieve a low-cost and easy-to-handle gamma-ray spectrometer, we developed a NaI(Tl) scintillator-type gamma-ray spectrometer with improved energy resolution using an unfolding method. We improved the unfolding method with a refined response function that considered the energy dependence of scintillation efficiency for secondary electrons produced by the interaction with the incident gamma rays. Response functions were calculated using a Monte-Carlo simulation code EGS5 with a mesh width of 5 keV in the energy range of 0 to 3 MeV. As a result, the energy resolution is about 10 keV and the measurement accuracy of gamma-ray fluence rate is almost constant at less than 10% at 0.3 MeV and above.

  • DEVELOPMENT OF SODIUM IODIDE SCINTILLATOR-TYPE GAMMA-RAY SPECTROMETER USING AN UNFOLDING METHOD WITH REFINED RESPONSE International conference

    Masateru Hayashi, Tetsushi Azuma, Makoto Sasano, Taisuke Makita, Masakazu Nakanishi and Hiroshi Nishizawa

    International Topical Workshop on Fukushima Decommissioning Research 2022  2022.10  The Japan Society of Mechanical Engineers, Atomic Energy Society of Japan

    　More details

    We developed a sodium iodide scintillator-type γ-ray spectrometer with improved energy resolution using an unfolding method for γ-ray spectroscopy and dosimetry during emergencies such as radiation leakage. As a result of measurements using 137Cs, 60Co, 133Ba, and 22Na radiation sources, the energy resolution is about 0.01 MeV and the measurement accuracy of γ-ray fluence rate is almost constant at less than 10% in at 0.3 MeV and above.

  • RADIOACTIVE CONTAMINATION INSPECTING SYSTEM FOR VEHICLE International conference

    Yoshitsugu Osawa, Hiroshi Nishizawa, Takahiro Kamito, Masateru Hayashi, Masakazu Nakanishi and Keiichi Matsuo

    International Topical Workshop on Fukushima Decommissioning Research 2022  2022.10  The Japan Society of Mechanical Engineers, Atomic Energy Society of Japan

    　More details

    We have developed a radioactive contamination inspecting system that automatically scans for radioactive contamination of vehicles entering and exiting radiation-controlled areas such as interim storage facilities in Fukushima prefecture. Although conventional manual measurement method took about 10 minutes by 10 operators to inspect a 10-ton truck, the developed system can automatically inspect it within 4 minutes.